Parentnoia
I'm Awesome
TL;DR
Seems like all you folks are over thinking this. Having lots of auxiliary lights and such is the equivalent of a huge stereo setup.
You need to worry about only two things. Alternator output while running, and the batteries' amp hours while it's off.
For alternators, look into DC Power and Mechman. They make high quality aftermarket alternators with decent idle output.
For batteries, look into XS Power. Great quality.
Both options are pricey, i will warn you of that. But the prices are worth. One XS Power battery as your main will do you just fine until you can get another.
As for hooking them up, just run one run of (preferably) 1/0 from positive to positive and one run of (preferably) 1/0 from negative to negative (or negative on the auxiliary battery to ground, the choice is yours). This is called parallel. Yes connecting them that way will drain them both at the same time, but doing it that way essentially doubles their amp hours. Therefore two batteries with 500 amp hours will produce essentially 1000 amp hours.
Imagine it this way, if you have a set of lights that draw 10 amps, no matter which battery you have them connected to, as long as the two (or more) batteries are connected in parallel, they will each only see 5 amps (or less, just divide the load by how many batteries you've got).
No need for fancy set ups and such.
Now, if you're truly worried about draining your batteries through parasitic draw, just set up a nice sized solenoid connected to a switch. It'll separate the auxiliary batteries from the main until you need them. I'll explain how to wire that if anyone's interested.
Seems like all you folks are over thinking this. Having lots of auxiliary lights and such is the equivalent of a huge stereo setup.
You need to worry about only two things. Alternator output while running, and the batteries' amp hours while it's off.
For alternators, look into DC Power and Mechman. They make high quality aftermarket alternators with decent idle output.
For batteries, look into XS Power. Great quality.
Both options are pricey, i will warn you of that. But the prices are worth. One XS Power battery as your main will do you just fine until you can get another.
As for hooking them up, just run one run of (preferably) 1/0 from positive to positive and one run of (preferably) 1/0 from negative to negative (or negative on the auxiliary battery to ground, the choice is yours). This is called parallel. Yes connecting them that way will drain them both at the same time, but doing it that way essentially doubles their amp hours. Therefore two batteries with 500 amp hours will produce essentially 1000 amp hours.
Imagine it this way, if you have a set of lights that draw 10 amps, no matter which battery you have them connected to, as long as the two (or more) batteries are connected in parallel, they will each only see 5 amps (or less, just divide the load by how many batteries you've got).
No need for fancy set ups and such.
Now, if you're truly worried about draining your batteries through parasitic draw, just set up a nice sized solenoid connected to a switch. It'll separate the auxiliary batteries from the main until you need them. I'll explain how to wire that if anyone's interested.